It is generally desired to release heat from a heat-emitting unit (e.g., a power amp) of communication equipment. For such function, an indoor type equipment uses a large capacity fan, while an outdoor type equipment uses a separate coding system.
FIG. 1 shows an apparatus for releasing heat from a heat-emitting unit 10 using a large capacity fan in conventional communication equipment. FIG. 1 shows a heat-emitting unit 10 with ventilation holes 11, a shelf 20 in which the heat-emitting unit 10 is set up, and a large capacity fan 30 for releasing heat by releasing air flowing inward through the ventilation holes 11.
The operation of the apparatus for releasing heat using a large capacity fan is described below. First, the heat-emitting unit 10 with the ventilation holes 11 is set up in the shelf 20. Then, air flows into the ventilation holes 11 and the large capacity fan 30 disposed on the rear side of the shelf 20 rotates at a high speed. This is to release heat from the heat-emitting unit 10 by releasing air in the heat-emitting unit 10 to the outside.
FIG. 2 is a schematic view of an apparatus for releasing heat using a water-coding scheme in conventional communication equipment, in which liquid is circulated. FIG. 2 shows a heat-emitting unit 40, a heat-exchanger 50, and a liquid-circulation pump 60.
The operation of the apparatus for releasing heat using a water-coding scheme, in which liquid is circulated, is described below. First, a pipe, through which liquid can pass, is set up in a predetermined position with respect to the heat-emitting unit 40. Then, the liquid-circulation pump 60 is driven so that the cooling liquid may flow into one end (i.e., inlet) of the pipe and flow out from the other end (i.e., outlet) of the pipe. The liquid that flows out of the pipe absorbs the heat from the heat-emitting unit 40. Then, the liquid is coded again by the heat-exchanger 50 and flows into the liquid-circulation pump 60. Thereafter, the liquid coded by the heat-exchanger 50 flows into the inlet of the pipe again through the liquid-circulation pump 60 and the heat-exchanger 50. By repeating this procedure, the apparatus removes heat from the heat-emitting unit 40.
The conventional apparatuses, however, have the following problems. First, the scheme using a large capacity fan undesirably produces bud noises. Further, it cannot be used if the heat density exceeds a certain limit (e.g. 30W/cm 3). Moreover, the use of a heat-sink leads to a relatively large size.
Second, the water-coding scheme is disadvantageous in that the system itself and its components are formed inside a body, which makes it difficult to repair them. Its units are not detachable. It is also disadvantageous in that the life span of a water pump for circulating liquid is relatively short compared to that of a general fan. The short life span of the water pump limits the life span of the entire system. Further, the coding liquid may leak to cause critical faults in the communication equipment.